1. Field
Aspects of the present disclosure relate to memory tagging, and more particularly to external memory tagging and stack ordering of memory tags.
2. Background
Some processor chips only include an internal memory such as read only memory (ROM) and random access memory (RAM) for code storage. These processor chips typically exclude an embedded flash memory. As a result, any flash code, e.g. ROM patch code and/or new application code, to be processed in the processor chips, may reside in an external flash device, for example, connected to the processor chips through a serial interface. The transfer of flash code to an internal memory of the processor chips is usually managed by a flash cache block. Because the flash device access speed is too low for execute-in-place code for many applications, flash code is transferred to the internal RAM of the processor chips before execution. Conventional implementations for mapping a location of the flash code in the internal RAM and for mapping a location of the flash code in the flash device are inadequate for handling patch codes and new application codes.